Rotary linen finish calender



Oct. 3, 1933` H. H. HANsoN ET ALy ROTARY LINEN FINISH CALENDER Filed Aug. 20, 1930 Geoff@ Ura/ven gyrneys Piuma oa. a, 1933 Y t 1.929.355 maar umm musa' carmen Hugo H. Hanson, Philadelphia, and George Craven, Conshohocken, Pa., asaignora to W. C.

Hamilton and Sons, tion of Pennsylvania Applicationl August 20,

11 Claims.

This invention relates to linen-huish calenvders, and more particularly to a machine for t producing linen-flnish paper in a continuous web by passingthe same through rolls.

It has been heretofore impossible to practically -produce a commercial grade of linenized paper approaching in quality the paper produced by the plate process by means of linen covered, or linen cover simulating rolls directly engaging a web of paper passing therebetween. A num'- ber of attempts have been made to produce such paper by the use of rolls but the closestapproach in a practical structure to the actual use of a roll consists in the use of rolls between which 15 linen webs are passed and between `the linen webs of which the paper web is passed. In some instances the linen web is an endless band and in other instances the linen web is a strip vvliiclik is transferred from one side of the machine to 2 0 the other. In the latter construction the length of the linen web employed will, of course, determine the length of the web of paper which'can be produced in a single operation. In the form` er construction where an endless band of linen is employed, some means must be provided to hold this band in a position preventing its buckling or cracking, suchmeans materially increasing the bulk of the machine and being otherwise disadvantageous. A machine employing such endless belts, however, very closely approximates the finish produced by the plate process of linenizing.

While attempts have been made to produce rolls having the linenizing surfaces directly applried thereto, such attempts have all been failures due to the fact that the rolls were either too hard or too soft. We have discovered that by making these rolls of a proper elastic density the linenizing surface produced by the plate process can be very closely approximated, if not duplicated, and a continuous web of linenized paper of high quality produced by passing the same through rolls with which they are in direct contact. Accordingly, an important object of the present invention is the production of a linen-surface roll having the proper density to enable its use in direct contact with the paper being linenized. y

VThis and other objects' we attain by the structure shown in the accompanying drawing wherein, for the purpose of illustration, we have shown a preferred embodiment of our invention and wherein:

'n 55 Fig. 1 is a side elevation of a linenizing calen- Mlquon, Pa., a corpora- 1930. serial No." 476,694 (o1. 10i-23)' der constructed ln accordance with our invention;

Fig. 2 is a front elevation thereof; v

3 is a longitudinal sectional view through one of the calender rolls; and

Fig. 4 is a fragmentary transverse sectional view through the roll.

Referringnow more particularly to the drawing, the numeral 10 generally indicates a linenizing calender machine, and 11 and 12 upper 05 and lower rolls mounted therein for rotation and maintained in pressure contact through a pressure-regulating member generally designated at 13, which may be of any suitable character. Each roll 11` and 12 has a linen cover 14 con- 70 sisting of from 1 to 5 plies of linen and a core 15 of such character that the elastic density of the roll at its outer surface gives a scleroscope \reading on the standard scleroscope of from 45 to 70. .The term elastic density is employed 76 as defining the density of the roll due to the fact that the actual density thereof is considerably less than the scleroscope test thereof would seem to indicate the increase in the apparent density of the roll being due to the inherent re- 80 siliency or elasticity thereof. The core 15 of the roll is preferably constructed from a fibrous, or fibrous base material and should have an elastic density in response to scleroscope tests with the standard scleroscope between 35 and S5 50. The bes't results are obtained by use of a core having an elastic density between 45 and 50, giving in a finished roll a surface density after application of the linen thereto of from. 45 to 70. It has been found that the elastic density of the completed roll increases with the number of plies of linen applied thereto and that best results are obtained where the number of plies of linen is such that the surface elastic density lies between 60 and '10.

In construction of the core, a base shaft 16 is preferably employed upon which, between end flanges 17 affixed to the shaft, a series of paper discs 18 is placed. The most efficient paper for use in this connection is manila rope paper and after a suflicient number of discs have been placed in position the core is axially compressed until the required elastic density thereof is obtained. The plies of linen are preferably individually applied and butt jointed as indicated in Fig. 4, each ply being glued in position and thoroughly dried before the next ply is placed in position thereon. Adjacent plies will have the joints thereof staggered as indicated. When the desired number of plies has been applied to the no lpressures, which are 40 to 60 tons.

roll, the surface of the roll is painted with a solution of formaldehyde preferably about a forty percent solution. l

Very satisfactory results have been obtained by the use of rolls constructed as described where the elastic density of the core by scleroscope reading was 47, and 5 plies of linen were applied to this core with a resultant final elastic density for the roll of 63 by scleroscope test. It may be noted that the quality of the produ t increases both with increase of the elastic desity of the core and with the increase of the plies of linen employed. The elastic the roll at its surface increases with of plies of linen applied thereto; for example, in the roll hereinbefore mentioned in which the core had an elastic density of 47, the density of the roll with one ply of linen is 50; with two plies, 53; with three plies, 56; with four plies, 60; and with 5 plies, 63. It will be understood that these iigures are those for a given roll and that a slight variation might occur in production of a second roll even though the core characteristics were the same, due to the diierences in manipulation number of density of the number and in application of the linen plies. Slight variations of this character do not. however, affect the finished product. It is desirable that, in the machine, the rolls 11 and 12 very closely approximate one another in elastic density.

In use of the apparatus, the pressure placed on the rolls is preferably such that adjacent surfaces of the rolls are slightly flattened at the point of contact. With a roll of the hardness described, this iattening occurs at usualflinenizing The previously moistened paper web to be linenized is then continuously passedl between the rolls, of which one is preferably driven and drives the other by frictional contact therewith' through the web W. The linenizing effect produced by such a machine, as hereinbefore stated, substantially duplicates that produced by the plate process and is of quite as high commercial value as the papers produced by machines employing linen bands Vpassed between adjacent surfaces of the rolls.

As the type of machine in which the rolls are employed is obviously unimportant and as the construction of the rolls themselves is capable of a considerable range of change and modication su without departing from the spirit of our invention, we do not wish to be understood as limiting ourselves thereto except as hereinafter claimed.

We claim: l. A linen covered non-ferrous calender roll for use in producing linenized paper having -an elastic surface density between 45 and 70 byscleroscope test.

2. A calender roll for a linenizing machine comprising a non-ferrous core having an elastic density between 35 and 50 by scleroscope test and one or more plies of linen covering said core, the roll having a surface density not less than 45.

3. A calender roll for a. linenizing machine comprising a non-ferrous core having an elastic density between 45 and 50 by scleroscope test and one or more plies of linen covering said core, the roll having a surface density not less than 45 by scleroscope test.

4. A linenizing calender comprising pressureengaged linen-surfaced non-ferrous rolls having an elastic density at the surfaces thereof of between 45 and 70 by scleroscope test.

5. A linenizing machine comprising linen-surfaced non-ferrous calender rolls in forcible engagement with one another, said rolls having a surface density by scleroscope test between 60 and '70.

6. A linenizing calender comprising pressureengaged linen-covered rolls, said rolls each comprising a non-ferrous core having an elastic density between 35 and 50 by scleroscope test and one or more plies of linen covering said core, the surface densities of the completed rolls lying between 45 and 70 by scleroscope test.

7. A linenizing calender comprising pressureengaged linen-covered rolls, said rolls each comprising a non-ferrous core having an elastic density between 35 and 50 by scleroscope test and one or more plies of linen covering said core, the surface densities of the completed rolls lying between 45 and 70 by scleroscope test, and being substantially identical in the two rolls.

8. A linenizing calender comprising linen-covered rolls adapted to engage one another through a strip of paper to be linenized, said rolls each comprising a non-metallic core and one or more plies of linen providing a continuous covering for said core, said rolls being of equal surface densities, a driving means connected to one of said rolls only, and means to urge the rolls into engagement with one another with a pressure rsuiiicient to cause a slight flattening of the rolls at the bite.

9. A linenizing calender comprisinglinen covered rolls, said rolls metallic core having an elastic density between 35 and 50 by scleroscope test and one or more plies of linen smoothly covering said core, the surface densities of the completed rolls lying between 45 and 70 by scleroscope test, driving means connected to one only of the rolls, and means for urging the rolls together with a pressure suflicient to cause a slight flattening of the rolls at the bite.

10. A calender roll for use .in linenizing machines comprising a non-metallic core having an elastic density between 35 and 50 by scleroscope test, and one or more plies of linen smoothly covering said core, the roll having an elastic density at its surface between 45 and 70 by scleroscope test.

11. A roll for a continuous linenizing calender comprising a non-metallic core and a continuous linen cover therefor comprising one or more plies of linen, said roll havinga hardness such that it forces the threads of linen into the treated paper at linenizing pressures, resists attening at pressures below linenizing pressures and has only a slight flattening at linenizing pressures.

each comprising a non' 

